It certainly is difficult but this is much easier than the previous SR titles. If you do get it spend some time looking through the interface, this isn't a game you will be able to pick up quick. You'll also want to play a small nation first run through. I played Yemen in my first game and found out a large amount about the economy and how it works. My next I played Saudi Arabia and attacked Yemen, it taught me a lot about the hex combat system. In my current game as Afghanistan I've learnt a huge amount about production and more.
It's a good game but it's also a long game. It'll give you more than enough time to work it out.